GD10P CO2 Gas Detector

 The Infrared (IR) gas detectors differ from all other models, because they utilise silicon based solid-state infrared sources. The complete opto-mechanical design construction is so stable that an ultra fast speed of response can be achieved whilst providing unparalleled service life and detector stability, thus saving on maintenance and service costs.
The Simtronics GD10 Series of gas detector offers the longest combined detector and IR source warranty on the market: 5 years warranty & 15 years on IR sources.


Technical Description – GD10P 

CO2 Gas Detector 

The GD10P fixed gas detector is the benchmark for combustible gas detection on offshore installations and has set the standard in the areas of safety, stability and low maintenance. The GD10P differs from other products because it uses silicone based solid-state infrared sources and has a complete optomechanical design and construction. The design is so stable it allows for an ultra-fast speed of response while providing unparalleled service life and detector stability, saving on maintenance and service costs.

A Closer Look

The GD10P concept  

The concept is based on measurement of infrared radiation passing through a volume of gas.  The GD10P employs a dual beam, dual wavelength measuring principle with separate optical detectors for maximum stability and reliability.  

Since different types of gas have unique absorption spectra, they can easily be identified by proper selection of an infrared wavelength at which absorption is measured.  Radiation at another wavelength measures the overall transmission through the optical system and the air volume. By comparing the transmission at the two wavelengths, the gas concentration in the air is determined. Having chosen a wavelength which is characteristic of one type of gas, other types of gas will not cause false alarms.   

Teledyne Oldham Simtronics GD10P CO2 Gas Detector

Using a solid-state IR source instead of a lamp ensures high reliability and long-term stability with no regular maintenance or calibration required during equipment lifetime.

Radiation from two infrared sources passes through two narrowband filters selecting a measuring wavelength and a reference wavelength. The sources are electronically chopped. Radiation is divided by a beam splitter into an internal and external path. The internal path is viewed by the compensation detector, and the external path is viewed by the measuring (main) detector. The compensation detector monitors and compensates for drift in sources or detectors. The main detector monitors the external measuring path and detects whether the selected gas is present.  

Teledyne Oldham Simtronics GD10P CO2 Gas Detector

The four signals, two from the compensation detector and two from the main detector, are amplified, digitised and fed to the microprocessor. The signals are used by the microprocessor to calculate the gas concentration. The gas response is then linearised and presented as either a voltage, a current or a digital output signal. Internal signals are compared with test limits to monitor electronics and optical parts. If values outside the test limits are found, specific error messages are given.

Optical filter characteristics remain constant over time, and drift in the other components is monitored and compensated by the dual wavelength, dual path concept. This means that the zero and gas span factory calibration will remain stable regardless of component drift, and that the detector needs no manual recalibration after factory calibration.  

How IR sources and detector elements can impact the performance of an IR gas detector  

The unique SimSource™ is a Simtronics patented solid state Silicon IR source used in all Simtronics IR gas detectors. This technology makes the GD10P the only Point IR Gas detector that does not require field calibration or recalibration during its lifetime. The GD10P has no user adjustable parts (i.e. no zero or span pots). It has been designed to require a minimum of maintenance.

A Closer Look

Ease of Maintenance 

The only necessary maintenance is to inspect visually that the Weather Protection is not clogged in heavily contaminated areas.  

In order to perform function test of the detector, a test gas can be applied through a 6 mm test nozzle on the front of the Weather Protection housing. Read the effect on the sensor output signal or through the gas detection system.  The GD10P has been designed for long-term stability, and in order to retain the high reliability of the GD10P it is only necessary to monitor the detector’s zero point and error messages from the detector. It does not even have the conventional zero and span pots. This feature prohibits anyone tampering with the settings of the detector.

Teledyne Oldham Simtronics GD10P CO2 Gas Detector

Every SimtronicsGD10P gas detectors employs two separate IR sources

In addition, the GD10P uses Lead Selenide detectors which are much more stable when exposed to rapid temperature changes than Pyroelectric sensors used by all other IR gas detectors. Lead Selenide will NOT give false readings if the detector is exposed to vibration. 

A Closer Look

Simtronics SimSource, solid-state silicone, patented, IR source:

  • Good IR emittance
  • Very long lifetime experienced RMTBF of more than 100 years based on close to 20 years of operational experience => no replacement of IR source.
  • Vibration and/or shock do not change characteristic nor reduce lifetime of the source
  • Source characteristics is stable over time, no degeneration or ageing effects => no zero or span re-calibrations over time
  • Can be electronically chopped at high frequencies (we do 50 Hz), which means high confidence gas measurements

Lead Selenide (PbSe – Simtronics choice)

  • Not acoustically sensitive, no possibility of false gas reading caused by vibration and/or shock
  • No spikes caused by temperature changes or thermal stress, hence no false gas readings
  • Quick acting, no limitation to chopping frequency of IR source
  • High raw gas measuring rate, possible single error readings do not cause false gas readings

Dual Wavelength and Dual Path

  • Simtronics GD10P uses 2 different IR sources to generate the active and reference signals for accurate gas detection – other manufactures utilize a single filament lamp.
  • Simtronics does not use Transmitter Receiver for Point IR gas detectors – this doubles the detection path making the reading a lot more reliable (Higher Signal to Noise Ratio).
  • No Calibration – Simtronics uses “SimSource™”, a Patented IR Source, to generate the IR signals Filament lamps require regular calibrations and have a limited lifespan.
  • 15 Years Extended Warranty on Simtronics Patented IR Sources – Our competitors warranty varies from 12 months to 3 years and some offer 5 years. Simtronics is the ONLY supplier of gas detection equipment that offer 15 years warranty on the IR sources.
  • Only Detector on the market that is SIL3 certified.
  • No need for a junction box or mounting hardware to install the detector. 
  • All 316SS stainless steel construction.
  • No special tools required to commission the GD10P.
  • Early Warning Dirty Optics signal is sent to the system when obscurity level reaches approximate 50% level – Detector remains online.
  • Warm up time in less than 60 seconds.
  • No Flame Arrestors or Teflon Hydrophobic Mesh around the optical chamber. Both these can clog up with dust and dirt and slow the gas from getting to the optical chamber.
  • IEC Ex Approved.
  • An Exe terminal integral compartment eliminating the cost of a special cable termination. 
  • Interchangeable with catalytic detectors using the existing cabling.
  • Fail-safe design – Error will not generate a false alarm.
  • Simtronics offers lowest Life Cycle Costs.
  • If calibrated to Methane, the GD10P will respond with a known output to other gases.
  • Allows operators to perform a functionality check while detector is installed from eye level.
  • Available with a Duct Mounting Kit for installation in ducts and HVAC. 

Life Cycle Cost Aspects

All Teledyne Oldham Simtronics SAS products are made in accordance with military and industrial specifications, and Simtronics is both ISO 9001 and AQAP-110 qualified.  

As a manufacturer and supplier of precision military and industrial electro-optical instruments to customers all over the world from 1969, we have gained extensive experience of implementing life cycle cost aspects as an important part of our product development. Important aspects here are the need for maintenance, repair and the overall expected lifetime for the gas detectors during normal operating conditions.  

Our IR gas detectors are based on a unique infrared source. The source is based on solid-state silicon, with a by SINTEF (Foundation for Scientific and Industrial Research at the Norwegian Institute of Technology) calculated expected lifetime of more than 60 years. This source is very resistant to vibration and is stable throughout its lifetime. The IR source is electronically chopped eliminating the need for moving parts. The all solid-state electronic design results in improved reliability, long-term stability and accuracy.  

We see the following features as important elements to reduce the cost of ownership as much as possible: 

  • No need for field re-calibration and re-zeroing 
  • No need for replacement of IR-sources 
  • High stability and reliability 
  • Simple maintenance 
  • Extended warranty 

Support and Maintenance 

Teledyne Oldham Simtronics SAS has support and maintenance available from ProDetec in Sydney Australia. With large quantities of products in service throughout the world, Simtronics remains proud of its dedication to cost effective through-life support. We can offer advice on and propose PM and test routines for all our gas detectors. 


We know that our gas detectors are critical component that has an important role within the end user’s complete safety management. This forms the basis for our design philosophy. Fail-safe design, high stability and reliability are important factors. A design that eliminates sporadic trips due to false gas alarms is an equally important part to consider.  

Declaration of warranty for Simtronics IR Gas Detectors

Five years full warranty on the sensor and 15 years extended warranty on the IR-sources. 

Teledyne Oldham Simtronics SAS guarantees the products mentioned above to be free from defects in material and workmanship for a period of five years from the time of their original purchase. In addition, they guarantee the IR source used in the products to be free from defects in material and workmanship for 15 years. If during this period of guarantee the products prove to be defective due to improper materials or workmanship, Teledyne Oldham Simtronics SAwill without charge for labour or parts, repair or (at Simtronics’ discretion) replace the product or its defective parts upon Teledyne Oldham Simtronics SAS  general terms and conditions. 

The warranty comes into effect from the day of shipment from Teledyne Oldham Simtronics SAS.

GD10P Response on Different HC-Gases

The following concentrations will give approximately full-scale output on a standard GD10P IR Gas Detector calibrated for 100% LEL methane:

Methane CH4 100% LEL
Propane C3H8 20% LEL
n-Butane C4H10 25% LEL
n-Hexane C6H14 80% LEL
Toulene C7H8 70% LEL
Styrene C8H8 120% LEL
Xylene C8H10 55% LEL
Ethyl Alcohol C2H6O 12% LEL
Ethyl Acetate C4H8O2 25% LEL
Methanol CH4O 15% LEL
JP.4 Jet fuel 60% LEL
98 oct. petrol C7H16 35% LEL
2. propanol C3H8O 25% LEL
Turpentine 40% LEL
Acetone C3H6O 60% LEL
Propene C3H6 60% LEL
Ethylene C2H4 110% LEL
White spirit (regular) 60% LEL
Ethanol C3H6O 15% LEL


Q. Does the GD10P use a lot of power?

A. The GD10P has a low power consumption of 140 mA (typical) to reduce the load on the UPS.

Q. For what applications is the GD10P best suited?

A. Marine and Jack up Rigs; FPSO/ FSO/ MOPU; Oil and Gas Offshore Drilling Rigs; Chemical and Petrochemical Plants; Waste Disposal; Gas Turbines; General Industry.

Q. Is the GD10P complicated to install?

A. No, this unit comes ready to use right out of the box, reducing overall installation time.

Q. Is the GD10P suitable for high-speed applications?

A. With a selectable response rate, this is the fastest IR point detector on the market making it ideal for speed critical applications.

Q. Does the system include preventative maintenance notifications?

A. The GD10P contains an early, dirty optics warning system that allows for improved preventative maintenance.

Q. Is field re-calibration required?

A. True dual path, double compensation optical design means that no field re-calibration is needed.

Q. Can I retrofit my application with the GD10P?

A. Yes! A bridge interface is available, which allows the GD10P to be directly connected to catalytic systems via the existing cabling and control modules.

Data Sheet – GD10P


Hover Box Element

Click edit button to change this text. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.


Hover Box Element

Click edit button to change this text. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.

U-Bolt Mounting Plate with Sunshade

Hover Box Element

GD10P Outline Drawing

Hover Box Element

U-Bolt Plate Adapter

Hover Box Element

GD10P Terminal Arrangement

Hover Box Element

GD10P Nozzle

Hover Box Element

GD10P Outline Drawing with Duct Kit

Hover Box Element

ABS Type Approval

Hover Box Element

Click edit button to change this text. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.

SIL Certificate

Hover Box Element

Click edit button to change this text. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.

IECEx Certificate of Conformity

Hover Box Element

Click edit button to change this text. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.